Nitrogen-rich carbon materials are very useful for applications such as supercapacitors, battery electrodes, oxygen reduction reaction supports for polymer electrolyte membrane (PEM) fuel cells and direct methanol fuel cells, and as sorbents for CO2 capture. They are also very useful as supports for other “active” materials such as Fe3O4, which yields synergistic CO2 capture and heavy metal absorption performance. Unfortunately nitrogen-rich carbonized materials are expensive to manufacture, normally requiring intense chemical treatments, such as acid boiling or exposure to high temperature ammonia vapors, in order to make their surfaces rich in nitrogen atoms. Moreover since these atoms are only at the outermost surface layer, the nitrogen-induced functionality wears out with prolonged use. Ideally the high (near 10% by weight) content would be in the bulk of the carbonaceous material, rather than at the surface. This would require high nitrogen content in the feedstock. A major economic advantage of such feedstock is that it would not require additional chemical treatments but would rely simply on pyrolysis and activation. Many such materials come from esoteric sources such as certain forms of seaweed.
Others have soaked eggshell membrane (ESM) in Co(NO3)2.6H2O and have pyrolyzed the whole structure. Also, ESM is often used as a template for other structures and is removed during pyrolysis.